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What is the difference between LGPL-2.1 and LGPL-3.0?

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TL;DR: Shipping an app that links an LGPL-3.0 library: Yes. Both are weak copyleft library licenses; LGPL-3.0 is written as extra permissions on top of GPL-3.0 and inherits its patent and anti-tivoization terms.

Is shipping an app that links an LGPL-3.0 library allowed under GNU Lesser General Public License v3.0?

Yes. Every use you described is granted by LGPL 3.0, and nothing you described is prohibited.

License: GNU Lesser General Public License v3.0 (LGPL-3.0-only, curated)

Duties: attribution, license_notice, share_alike, source_disclosure

How do LGPL-2.1-only and LGPL-3.0-only compare?

The table lists each license's duties and notes side by side.

LicenseDutiesNotes
LGPL-2.1-onlyattribution, license_notice, state_changes, share_alike, source_disclosureThe copyleft duties apply to the library and modified versions of it, not to an application that only links to it (section 5). Each recipient receives a license from the original licensor; sublicensing is not allowed (section 10).
LGPL-3.0-onlyattribution, license_notice, share_alike, source_disclosureThe copyleft duties apply to the library and modified versions of it, not to an application that only links to it.

Combined in one work: needs_review.

What else should I know?

What are the sources?

How can I check it myself (free, no key)?

{
  "tool": "check_license",
  "arguments": {
    "license": "LGPL-3.0-only",
    "intended_use": {
      "commercial_use": true,
      "redistribution": true
    }
  }
}

Computed from a2ally's license profiles; not legal advice. JSON · Markdown

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